Radiotelegraphy



H. F. ELLIOTT.

RADIOTELEGRAPHY.

APPLICATION FILED MAR. 23, 1920.

1,35,883 yatemeas tfn, 1920.

WITNESS IN VEN TOR HFELL mrr ATTORNEYS UNITED STATES PATENT OFFICE.

HAROLD F. ELLIOTT, OF PALO ALTO, CALIFORNIA, ASSIGNOR' TO, AUGUSTUS TAYLOR,

' OF SAN FRANCISCO, CALIFORNIA.

RADIOTE-LEGRAPHYY.

' Application filed March 23,

To all whom it may conceriz:

Be it known that I, HAROLD F. ELLIOTT, a citizen of the'United States, and a resident of-Palo Alto, county of Santa Clara, and

State of California, have invented certain new and useful Improvements innRadiotelegraphy, of which the following is a specifi: cation.-

The invention relates to signaling and particularly to means for signaling with arc radio transmitters.

An object of the invention is to provide means for signaling by interrupting and reestablishing the arc.

Another object of the invention is to pro vide signaling means of the above men tioned type in which all moving parts are.

at 'earth potential.

The invention possesses other advantageous features, some-of which, with the foregoing, will be set forth at length in the following description, where I shall outline in closed in the chamber 10.

. generator 5 remains the same when the arc is burnlng and when the shunt circuit 1s] full that form of the invention which I have selected for illustration in the drawing accompanying and forming part of the present specification.

Thedrawing is a diagrammatic representation of one form of signaling system of my invention.

The transmission system comprises a Poulsen arc oscillation generator 2, which is grounded on the negative side and. connected on the positive side to the antenna 3 through the variable inductance 1. Direct current is supplied to the are by the generator 5, andcombined magnetic and choke coils 6 are arranged in'the positive lead from the generator, so that the arc is subjected to a strong transverse magnetic field. I The are is formed between the anode 7 and the 'cathode 8 in shunting the arc is a circuit containing a resistor 9 and means for opening and closing the circuit. The value of the resistance 9 is preferably so adjusted that the load on the closed. The means for opening and closing the shunt circuit comprises a stationary electrode '12 connected to the anode? through the resistor 9, which electrode isarranged within the arc chamber adjacent the anode.

Disposedadjacent the electrode 12 is a mov-{ able electrode 13 which is connected to the cathode 8 or to the groundedside of the genwithout danger. "[Iclaim:

1. In an arc radio generator, an anodeand tween theanode and cathode.

1920. Serial No. 368,193. I

'era'tor, the electrode 13. being also wholly or present instance the electrode being moved by a signaling key 14 connected to the electrode by thelink 15 and lever 16. The'electrode 13 is normally held in contact with the electrode 12 by a spring 17 so that when the key is depressed, the electrodes 12 and 13 are separated. ,As' the resistance circuit opened, an arc is produced between the electrodes 12 and 13, and this arc is blown into contact with the electrodes? and 8 by the magnetic field, thereby igniting the main arc. a

By'this arrangement of parts, the movable electrode and all m'ovable .parts are at earth potential, thus overcoming the difliculty of insulating them from earth and also permitting the adjustment of the movable electrode a cathode between which an arc is formed, a

stationary electrode arranged adjacent the anode and connected thereto, a resistor in the circuit between the stationary electrode and the anode, a movable electrodearranged adjacent the stationary electrode and connected 'to the cathode and means for moving the Specification or Letters Patent. Pat t d Sept. 14,1920.

moving electrode to .make and break contact between the electrodes.

' 2. In an arc radio generator, an anode and a cathode between whiclfl an arc is formed, a resistance circuit shunted around the arc, a pair of electrodes in said circuit having their points of contact adjacent the arc gap and means for separating said electrodes whereby an arc is formed which ignites the arcbe- 3. In an arc radio generator, an anode and acathode having an arc gap between them,

means for subjecting the arc gap to a strong transverse magnetic field, a resistance circuit 7 shunting the arc and a pair of separable electrodes in said circuit disposed with their points of separation in the magnetic field adjacent the arc gap. v

4. Inan arcradio generator, a chamber inclosing an anode and a cathodehaving an arc gap between them, a source of current supply connected to the anode and cathode, means for subjecting the arc gap to a strong transverse magnetic field, a stationary electrode arranged in the chamber adjacent the anode and connected to the anode, a resistor in the circuit between the stationary electrode and the anode, a movable electrode connected to the cathode and arranged within saidchamber, the oints of contact of said electrodes being in t e magnetic field and adjacent the arc gap, and moving the movable electrode to'ope'n and close the resistance circuit, opening of the re- L SlStflllCG c1rcu1t causlng an are between the means for v electrodes which is" blown hy the magnetic field into the arc gap, 'g'nitmg the are between 'the anode and cathode.

In'testimony whereof, I have hereunto set 15'- y n t alo lto, California, this 12th day of March, 1920. I H o r g Q HAROLD r. ELLIOTT. In presence of-' CARL E. Sononz, RUBY SHEPARD. 

